new boston hazard mitigation plan · the springfield hazard mitigation plan is a planning tool for...

Town of Springfield,

New Hampshire Hazard Mitigation Plan

Plan submitted to FEMA May 2008 FEMA Approval August 2008

Town of Springfield Hazard Mitigation

Committee

Upper Valley Lake Sunapee Regional Planning

Commission

Snow Rolling Main Street (aka Howard Avenue) 1925

Town of Springfield Hazard Mitigation Plan – 2008 March 2008 APPROVED PLAN

TABLE OF CONTENTS I. INTRODUCTION..................................................................................................................................................................................................................... 1

A. BACKGROUND.................................................................................................................................................................................................................... 1 B. PURPOSE .............................................................................................................................................................................................................................. 1 C. HISTORY .............................................................................................................................................................................................................................. 1 D. SCOPE OF THE PLAN.......................................................................................................................................................................................................... 2 E. METHODOLOGY................................................................................................................................................................................................................. 2 F. HAZARD MITIGATION GOALS......................................................................................................................................................................................... 5 G. ACKNOWLEDGEMENTS ................................................................................................................................................................................................... 6

II. COMMUNITY PROFILE........................................................................................................................................................................................................ 7 A. INTRODUCTION.................................................................................................................................................................................................................. 7 B. DEVELOPMENT TRENDS .................................................................................................................................................................................................. 9

III. HAZARD IDENTIFICATION.......................................................................................................................................................................................... 12 A. WHAT ARE THE HAZARDS IN SPRINGFIELD? ............................................................................................................................................................ 12 B. DESCRIPTIONS OF HAZARDS ........................................................................................................................................................................................ 12

Dam Failure.............................................................................................................................................................................................................................. 13 Flooding.................................................................................................................................................................................................................................... 15 Hurricane.................................................................................................................................................................................................................................. 19 Tornado & Downburst .............................................................................................................................................................................................................. 21 Thunderstorms .......................................................................................................................................................................................................................... 23 Severe Winter Weather.............................................................................................................................................................................................................. 23 Earthquake................................................................................................................................................................................................................................ 27 Landslide................................................................................................................................................................................................................................... 28 Drought ..................................................................................................................................................................................................................................... 28 Extreme Heat ............................................................................................................................................................................................................................ 29 Erosion...................................................................................................................................................................................................................................... 30 Wildfire ..................................................................................................................................................................................................................................... 31 Natural Water & Air Contaminants .......................................................................................................................................................................................... 32 Hazardous Materials Spills....................................................................................................................................................................................................... 34

C. HAZARD RISK RATINGS ................................................................................................................................................................................................. 35 Assessing Probability ................................................................................................................................................................................................................ 35 Assessing Vulnerability ............................................................................................................................................................................................................. 36 Assessing Risk ........................................................................................................................................................................................................................... 36

IV. CRITICAL FACILITIES/LOCATIONS......................................................................................................................................................................... 39 V. DETERMINING HOW MUCH WILL BE AFFECTED.................................................................................................................................................... 41


A. IDENTIFYING VULNERABLE FACILITIES ................................................................................................................................................................... 41 B. IDENTIFYING VULNERABLE SPECIAL POPULATIONS ............................................................................................................................................ 42 C. POTENTIAL LOSS ESTIMATES....................................................................................................................................................................................... 43

Dam Failure – Low Risk - $0 Estimated Cost........................................................................................................................................................................... 43 Flooding – Medium Risk - $1,538,700 Estimated Cost............................................................................................................................................................. 43 Hurricane – Low/Medium Risk – No Recorded or Estimated Cost........................................................................................................................................... 43 Tornado & Downburst – Low/Medium Risk – No Recorded or Estimated Cost....................................................................................................................... 44 Thunderstorm/Lightening/Hail – Low/Medium Risk – No Recorded or Estimated Cost .......................................................................................................... 44 Severe Winter Weather – Medium Risk – No Recorded or Estimated Cost .............................................................................................................................. 44 Earthquake – Low Risk - $1,500,000 Estimated Cost ............................................................................................................................................................... 44 Landslide – Low Risk – No Recorded or Estimated Cost.......................................................................................................................................................... 45 Drought - Low Risk – No Recorded or Estimated Cost............................................................................................................................................................. 45 Extreme Heat – Low Risk – No Recorded or Estimated Cost ................................................................................................................................................... 45 Erosion – Low/Medium Risk – No Recorded or Estimated Cost............................................................................................................................................... 45 Wildfire – Low/Medium Risk – No Recorded or Estimated Cost .............................................................................................................................................. 45 Natural Water & Air Contaminants - Low Risk – No Recorded or Estimated Cost.................................................................................................................. 46 Hazardous Material Spills - Low Risk – No Recorded or Estimated Cost................................................................................................................................ 46

VI. EXISTING MITIGATION ACTIONS............................................................................................................................................................................. 47 VII. GOALS AND NEWLY IDENTIFIED MITIGATION ACTIONS................................................................................................................................ 50

A. GOALS & OBJECTIVES .................................................................................................................................................................................................... 50 B. POTENTIAL MITIGATION ACTIONS ............................................................................................................................................................................. 51 C. SUMMARY OF CRITICAL EVALUATION...................................................................................................................................................................... 51

VIII. PRIORITIZED IMPLEMENTATION SCHEDULE ..................................................................................................................................................... 53 IX. ADOPTION & IMPLEMENTATION OF THE PLAN ................................................................................................................................................. 55

A. IMPLEMENTATION THROUGH EXISTING PROGRAMS ............................................................................................................................................ 55 B. CONTINUED PUBLIC INVOLVEMENT.......................................................................................................................................................................... 55


TABLES

Table II-1: AREA POPULATION TRENDS........................................................................................................................................... 11 Table II-2: POPULATION PROJECTIONS FOR SPRINGFIELD....................................................................................................... 11 Table II-3 : OCCUPIED HOUSING UNIT PROJECTIONS BY TYPE FOR SPRINGFIELD.............................................................. 11 Table II-4: TOTAL HOUSING UNIT PROJECTIONS BY OCCUPANCY FOR SPRINGFIELD....................................................... 11 Table III-1: DAMS – LOW RISK ............................................................................................................................................................ 13 Table III-2: FLOODING – FEMA DISASTER DECLARATIONS........................................................................................................ 17 Table III-3: FEMA FLOOD INSURANCE RATE MAP SPECIAL FLOOD HAZARD AREAS ......................................................... 17 Table III-4: LOCALLY DEFINED FLOODING – MEDIUM RISK...................................................................................................... 18 Table III-5: HURRICANES & TROPICAL STORMS – LOW/MEDIUM RISK................................................................................... 20 Table III-6: TORNADOES IN SULLIVAN COUNTY – LOW RISK.................................................................................................... 22 Table III-7: SEVERE WINTER WEATHER – LOW/MEDIUM RISK.................................................................................................. 25 Table III-8: EARTHQUAKES – LOW/MEDIUM RISK ........................................................................................................................ 27 Table III-9: DROUGHT – LOW RISK .................................................................................................................................................... 29 Table III-10: EXTREME HEAT – LOW/MEDIUM RISK ..................................................................................................................... 30 Table III-11: RADON – LOW RISK........................................................................................................................................................ 33 Table III-12: HAZARDOUS WASTE GENERATORS – LOW RISK................................................................................................... 34 Table III-13: PROBABILITY OF HAZARD........................................................................................................................................... 35 Table III-14: VULNERABILITY OF EXISTING DEVELOPED AREAS............................................................................................. 36 Table III-15: RISK ASSESSMENT ......................................................................................................................................................... 38 Table IV-1: EMERGENCY RESPONSE FACILITIES, SERVICES & STRUCTURES....................................................................... 39 Table IV-2: NON-EMERGENCY RESPONSE FACILITIES & STRUCTURES.................................................................................. 40 Table IV-3: FACILITIES & POPULATIONS TO PROTECT................................................................................................................ 40 Table V-1: VULNERABILITY OF EXISTING DEVELOPED AREAS................................................................................................ 41 Table VI-1: EXISTING MITIGATION ACTIONS................................................................................................................................. 47 Table VI-2: PRIORITIZING EXISTING MITIGATION STRATEGY IMPROVEMENTS ................................................................. 49 Table VII-1: PRIORITIZING PROPOSED MITIGATION STRATEGIES............................................................................................ 52 Table VIII-1: PRIORITIZED IMPLEMENTATION SCHEDULE OF EXISTING PROGRAM IMPROVEMENT ACTIONS.......... 53


APPENDICES

Appendix A: Technical Resources Appendix B: Technical and Financial Assistance Appendix C: Matrix of Federal All-Hazards Grants Appendix D: Meeting Documentation Appendix E: Map of Past and Potential Hazard Event Areas and Critical Facilities Appendix F: Map of Wildland – Urban Interface for Wildfire Hazard Areas Appendix G: Map of Eastman Dam Inundation Area


Springfield Town Offices, Library, Kindergarten, and

Police Station Springfield Town Hall

Springfield Public Beach – Kolelemook Lake Springfield Fire, Highway, & Safety Building


I. INTRODUCTION

A. BACKGROUND The New Hampshire Homeland Security & Emergency Management (NH HSEM) has a goal for all communities within the State of New Hampshire to establish local hazard mitigation plans as a means to reduce future losses from natural or man-made hazard events before they occur. The NH HSEM has provided funding to the Upper Valley Lake Sunapee Regional Planning Commission (UVLSRPC), to prepare local Hazard Mitigation Plans with several of its communities. UVLSRPC began preparing a local Hazard Mitigation Plan for the Town of Springfield in October 2007. The Springfield Hazard Mitigation Plan serves as a strategic planning tool for use by the Town of Springfield in its efforts to reduce future losses from natural and/or man-made hazard events before they occur. This Plan does not constitute a section of the Master Plan. The Springfield Hazard Mitigation Committee prepared the Springfield Hazard Mitigation Plan with the assistance and professional services of the UVLSRPC under contract with the NH HSEM operating under the guidance of the Federal Emergency Management Agency (FEMA). After a public hearing held in the Springfield Town Offices, the Springfield Board of Selectmen adopted the plan on June 24, 2008. B. PURPOSE The Springfield Hazard Mitigation Plan is a planning tool for use by the Town of Springfield in its efforts to reduce future losses from natural and/or man-made hazards. This plan does not constitute a section of the Town Master Plan, nor is it adopted as part of the Zoning Ordinance. C. HISTORY On October 30, 2000, President Clinton signed into law the Disaster Mitigation Act of 2000 (DMA 2000). The ultimate purpose of DMA 2000 is to:

• Establish a national disaster mitigation program that will reduce loss of life and property, human suffering, economic disruption, and disaster assistance costs resulting from disasters, and

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• Provide a source of pre-disaster mitigation funding that will assist States and local governments in accomplishing that purpose.

DMA 2000 amends the Robert T. Stafford Disaster Relief and Emergency Assistance Act by, among other things, adding a new section: 322 – Mitigation Planning. This places new emphasis on local mitigation planning. It requires local governments to prepare and adopt jurisdiction-wide hazard mitigation plans as a condition to receiving Hazard Mitigation Grant Program (HMGP) project grants. Local governments must review and if necessary, update the mitigation plan annually to continue program eligibility. Why develop a Mitigation Plan? Planning ahead to lessen or prevent a disaster will reduce the human, economic, and environmental costs. The State of NH is vulnerable to many types of hazards, including floods, hurricanes, winter storms, wildfires, wind events, and earthquakes. All of these types of events can have significant economic, environmental, and social impacts. The full cost of the damage resulting from the impact of natural hazards – personal suffering, loss of lives, disruption of the economy, and loss of tax base – is difficult to quantify and measure. D. SCOPE OF THE PLAN The scope of the Springfield Hazard Mitigation Plan includes the identification of natural hazards affecting the Town, as identified by the Springfield Hazard Mitigation Committee. The hazards were reviewed under the following categories as outlined in the State of New Hampshire Hazard Mitigation Plan:

I. Flooding (Including hurricanes, 100-year floodplain events, debris-impacted infrastructure, erosion, mudslides, rapid snow pack melt, river ice jams, dam breach and/or failure)

II. Wind (Including hurricanes, tornadoes, “Nor’easters,” downbursts and lightning) III. Fire (Including forest fires and issues such as isolated homes and residential areas) IV. Ice & Snow Events (Including heavy snow storms, ice storms, and “Nor’easters,”) V. Earthquake (Including landslides and other geologic hazards related to seismic activity) VI. Other Events (Including hazardous materials events and terrorism)

E. METHODOLOGY Using the Guide to Hazard Mitigation Planning for New Hampshire Communities (2002), as developed by the Southwest Regional Planning Commission (SWRPC), the Springfield Hazard Mitigation Committee, in conjunction with the UVLSRPC, developed the

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content of the Springfield Hazard Mitigation Plan by tailoring the nine-step process set forth in the guidebook appropriate for the Town of Springfield. Many FEMA resources and multiple State and Federal websites were also used as well as the Springfield Master Plan and Emergency Management Plan. The Committee held a total of three posted meetings beginning in October 2007 and ending in February 2008. All meetings were posted at the Town Office and post office inviting the general public. A notice was placed in the Valley News for the January 2008 meeting, and notices were sent to the Town Offices of neighboring towns to invite town officials. Town officials and local residents attended. For the publicly posted meeting agendas see Appendix D: Meeting Documentation. The public will continue to be involved in future revisions as meetings will be posted publicly and advertised in local newspapers. FEMA granted conditional approval on June 18, 2008. The Springfield Board of Selectmen adopted the Plan, contingent upon FEMA final approval, on 6/24/08. Prior to the Town of Springfield approving the Plan, a public hearing was held to gain additional input from the citizens of Springfield and to raise awareness of the ongoing hazard mitigation planning process. The following hazard mitigation meetings were vital to the development of this Plan:

October 4, 2007 (Meeting between UVLSRPC, Selectboard, & Hazard Mitigation Committee) October 24, 2007 (Hazard Mitigation Committee) December 5, 2007 (Meeting between Emergency Management Director & UVLSRPC) January 8, 2008 (Meeting between Administrative Assistant & UVLSRPC) January 24, 2008 (Hazard Mitigation Committee) January 30, 2008 (Meetings with Road Agent and Administrative Assistant with UVLSRPC) February 21, 2008 (Hazard Mitigation Committee to review draft plan)

To complete this Plan, the Hazard Mitigation Committee followed the following planning steps: Step 1: Identify and Map the Hazards (October 2007) Committee members identified areas where damage from natural disasters had previously occurred, areas of potential damage, and human-made facilities and infrastructure that were at risk for property damage and other risk factors. A GIS-generated base map provided by the UVLSRPC was used in the process. Step 2: Determine Potential Damage (October 2007) Committee members identified facilities that were considered to be of value to the Town for emergency management purposes, for provision of utilities and services, and for historic, cultural and social value. A GIS-generated map was prepared to show critical facilities identified by the Springfield Hazard Mitigation Committee. A summary listing of “Critical Facilities” is presented in Chapter IV. Costs were determined for losses for each type of hazard.

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Step 3: Identify Mitigation Plans/Policies Already in Place (October 2007) Using information and activities in the handbook, the Committee and UVLSRPC staff identified existing mitigation strategies which are already implemented in the Town related to relevant hazards. A summary chart and the results of this activity are presented in Chapter VI. Step 4: Identify the Gaps in Protection/Mitigation (October 2007) Existing strategies were then reviewed for coverage, effectiveness and implementation, as well as need for improvement. Some strategies are contained in the Emergency Action Plan and were reviewed as part of this step. The result of these activities is presented in Chapter VI. Step 5: Determine Actions to be Taken (January 2008) During an open brainstorming session, the Hazard Mitigation Committee developed a list of other possible hazard mitigation actions and strategies for the Town of Springfield. Ideas proposed included policies, planning, and public information. A list of potential mitigation strategies can be found in Chapter VII. Step 6: Evaluate Feasible Options (January 2008) The Hazard Mitigation Committee evaluated the proposed actions based on eight criteria derived from the criteria listed in the evaluation chart found on page 27 of the Guide to Hazard Mitigation Planning for New Hampshire Communities. The eight criteria used for evaluation of potential mitigation strategies are listed in Chapter VII. Each strategy was rated high (3), average (2), or low (1) for its effectiveness in meeting each of the eight criteria (e.g., Does the mitigation strategy reduce disaster damage?). Strategies were ranked by overall score for preliminary prioritization then reviewed again under step eight. The ratings of the potential mitigation strategies can be found in Chapter VII. Step 7: Coordinate with other Agencies/Entities (Ongoing) UVLSRPC staff reviewed the Springfield Master Plan. This was done in order to determine if any conflicts existed or if there were any potential areas for cooperation. Town staff that was involved in preparing the Emergency Operations Plan participated in the hazard mitigation meetings, to avoid duplication and to share information. Step 8: Determine Priorities (January 2008) The Committee reviewed the preliminary prioritization list in order to make changes and determine a final prioritization for new hazard mitigation actions and existing protection strategy improvements identified in previous steps. UVLSRPC also presented recommendations for the Committee to review and prioritize. These are provided in Chapter VIII.

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Step 9: Develop Implementation Strategy (January 2008) Using the chart provided under step nine of the Guide to Hazard Mitigation Planning for New Hampshire Communities, the Committee created an implementation strategy which included person(s) responsible for implementation (who), a schedule for completion (when), and a funding source and/or technical assistance source (how) for each identified hazard mitigation actions. The prioritized implementation schedule can be found in Chapter VIII. Step 10: Adopt and Monitor the Plan UVLSRPC staff compiled the results of steps one through nine in a draft document, as well as helpful and informative materials from the State of New Hampshire Natural Hazard Mitigation Plan (2004), which served as a resource for the Springfield Hazard Mitigation Plan. The process for monitoring and updating the Plan can be found in Chapter IX. F. HAZARD MITIGATION GOALS The Town of Springfield Hazard Mitigation Committee reviewed the hazard mitigation goals for the State of New Hampshire, and revised them for Springfield. They are as follows:

1. To protect the general population, the citizens of the town and guests, from all natural and man-made hazards.

2. To reduce the potential impact of natural and man-made disasters on the town’s critical support services, critical facilities, and infrastructure.

3. To reduce the potential impact of natural and man-made disasters on the town’s economy.

4. To reduce the potential impact of natural and man-made disasters on the town’s natural environment.

5. To reduce the potential impact of natural and man-made disasters on the town’s specific historic treasures and interests as well

as other tangible and intangible characteristics which add to the quality of life of the citizens and guests of the town.

6. To identify, introduce and implement cost effective hazard mitigation measures so as to accomplish the town’s goals (above) and to raise the awareness and acceptance of hazard mitigation.

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G. ACKNOWLEDGEMENTS The following people participated in the development of this plan as the Hazard Mitigation Committee:

• Frank Anderson, Town of Springfield Emergency Management Director • Bradley Butcher, Town of Springfield Road Agent • Tom Duling, Town of Springfield Health Officer • Tim Julian, Town of Springfield Chief of Police • Janet Roberts, Town of Springfield Administrative Assistant • John Chiarella, Town of Springfield Selectman • Gene Hayes, Town of Springfield ZBA • Robert Anderson, Town of Springfield Chair Selectmen • Dallas Patten, Town of Springfield Fire Department Chief • John Trachy, Town of Springfield Conservation Commission • Ken Jacques, Town of Springfield Planning Board & Twin Lake Villa Representative • Jeremy LaPlante, NH Homeland Security & Emergency Management Field Representative • Courtney Daniell, Upper Valley Lake Sunapee Regional Planning Commission • Victoria Davis, Upper Valley Lake Sunapee Regional Planning Commission

The Hazard Mitigation Committee was composed of local officials, representatives from state agencies (NH HSEM), citizens of Springfield and staff representatives of the UVLSPRC for meeting facilitation and plan development. Neighboring communities, agencies, businesses, academia, non-profits and other interested parties were invited to participate through the public posting of meeting times and agendas or through invitation. Historical information, relevant data and potential future mitigation strategies were contributed by all parties involved in the planning process. For a record of all meeting topics see Appendix D: Meeting Documentation. The staff representative of the UVLSRPC gathered all information from local officials, agency representatives and public input and compiled the information to develop the Plan.

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II. COMMUNITY PROFILE

A. INTRODUCTION1 The Town of Springfield is located in Sullivan County, north of the Towns of New London and Sunapee off I-89 between Concord and Lebanon. The Town encompasses approximately 28,479 acres or 44.5 square miles in area including close to 1,000 acres of surface water. Springfield has one of the largest land areas in the Region. The Town can be generally characterized as high, hilly, wooded, and rural with several water bodies and large acreages of forest cover mixed with occasional individual homes and groups of houses along the road system. Approximately 29% of the Town is conserved land. Most of Springfield is in the Sugar River Watershed. The northeastern portion of the Town is within the Blackwater River Watershed and the Smith River Watershed. A very small area in the northwestern portion of Town is within the Mascoma River Watershed. There are no rivers in Springfield. Major brooks are Gove, Bog, Carter, Sanders, Kidder, and Colcord Brooks. Several lakes and ponds are scattered throughout the town: Kolelemook Lake (98 acres, 1,387’ el.), Baptist Pond (99 acres, 1,266’ el.), Bog Brook Reservoir (94 acres, 990’ el.), Star Lake (67 acres, 1,286’ el.), Morgan Pond (34 acres, 1,682’ el.), Dutchman Pond (28 acres, 1,543’ el.), and, and several lesser ponds such as Little Stocker Pond (18 acres, 1,190’ el.), Palazzi Pond (16 acres, 1,037’ el.), McAlvin Pond (10 acres, 1,335’ el.) and other unnamed ponds. There are also the McDaniels Waterfowl Marsh Wildlife Management Area around the Bog Brook Reservoir and a small portion of Little Sunapee Lake which is primarily located in New London. High elevations and steep slopes have encouraged the preservation of forest tracts particularly in the eastern portion of town. Although there is little “virgin” timber in Town, older reforestation has left substantial stands in the area in and around Gile Memorial Forest and to the southwest between I-89 and New London Road. Approximately 85% of the town is covered with forests (1998 Orthophotos). Lumbering is a major industry in Springfield. Town facilities include the Town Office Building which houses the town offices, the library, police department, and kindergarten. The fire station and highway garage are housed in the same building. The Town/Meeting Hall was moved to its current site in 1851. A church is located on its second floor. The Historical Society’s collection is housed in a small building formerly a one-room schoolhouse. The old concrete highway garage building is used as storage for both the Highway and Cemetery Departments.

1 Springfield Town Master Plan 2005 and Springfield Hazard Mitigation Committee

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The Town of Springfield does not operate a public municipal water or sewer system for the entire town. However, the New London-Springfield Water System Precinct provides water to the Twin Lake Villa area in the southeast corner of Springfield which currently services 20-25 private seasonal and year-round homes in Springfield as well as a summer hotel and 15 rental houses. Some of the rental houses are winterized and rented out in the winter for skiing as well as in the warmer months. This water system extends into New London where the water system also serves five rental homes belonging to Twin Lake Villa as well as New London’s commercial area including private residences, the New London Hospital, and Colby Sawyer College. The well field for the system is located on a peninsula in Springfield extending into Little Sunapee Lake. These wells feed the main pump station and a million gallon water tank located in Springfield and the auxiliary pump station and a one-half million gallon water tank located in New London. There is a back-up generator at each pump station. The Springfield water tank could supply two to three days worth of water for residential use.

The Village District of Eastman provides a water system serving approximately 1,300 units—most of the units are located in the Town of Grantham though several units are located in the Town of Springfield and some units are located in the Town of Enfield. The well field and treatment facility are located in Springfield. The publicly maintained roads total about 68 miles. The Town maintains 37 of those miles. Several roads are part of the State system: Route 4A, Route 114, Georges Mills Road, and Four Corners Road. Figure II-1: Locus Map of Springfield

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Springfield is currently not a participating member of the National Flood Insurance Program. The Town of Springfield is currently working toward become a participating member of the NFIP. As part of the National Flood Insurance Program (NFIP), Flood Hazard Boundary Maps were prepared for the Town on November 8, 1977. Updated maps for all towns within Sullivan County were finalized in 2006. These maps identified those areas in town that fall within Zone A, which are Special Flood Hazard Areas inundated by the 100-year flood, with base flood elevations not determined. Examination of the floodplain maps indicates that there are relatively few areas that would be inundated by a 100-year flood. However, the Springfield Hazard Mitigation Committee identified several other areas which have been flooded. The Special Flood Hazard Areas and the Committee identified flood areas are shown in Appendix E. B. DEVELOPMENT TRENDS Examination of the U.S. Census Data indicates that population grew by 48% from 1980 to 1990 going from a population of 532 to 788. From 1990-2000, population increased by 20%. Using NH Office of Energy and Planning 2005 population estimate of 1,060 for the Town, population grew by approximately 12% between 2000 and 2005. The predominant land use in Springfield is residential. Most of this development is in year-round single family homes although there are substantial seasonal homes. The greatest density of development occurs along Route 114 in the southern portion of town. The remaining development occurs along other road frontage in the western portion of town. The Eastman development is predominantly located in the neighboring Town of Grantham. However, this development spills over into a western section of Springfield with several lots (developed and undeveloped) on private roads. Two new developments are currently being proposed to the Town: a development of about 15 homes on the east side of Route 114 below Kolelemook Lake and a 20-30 home development between Town Farm Road, Four Corners Road, and Route 114. The Twin Lake Villa, Incorporated owns a 150 acre parcel behind its hotel which could potentially be developed in the future. If any of these potential developments are approved, they will be located in elevated areas away from flood hazards. Several factors have played, and will continue to play, an important role in the development of Springfield. These include the existing development pattern and availability of land for future development; the present road network; physical factors such as steep slopes, soil conditions, wetlands, and aquifers; land set aside for conservation; and the effectiveness of the zoning ordinance to control growth in areas less desirable to development such as on steep slopes. These factors have an impact, both individually and cumulatively, on where and how development occurs. Most of the hillsides have steep slopes and shallow soils not suitable for development, but the current zoning ordinance does not address this issue and allows development in these areas. Due to growth pressures in the region, the recreational lakes in Springfield,

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a nearby ski area, and Springfield’s proximity to I-89, the Town is a desirable location for future development. Review and amendment of land use regulations will help the Town determine the density and location of future development taking into account many factors including steep slopes and known hazard event areas such as flood zones. The following tables provide the current population and number of housing units in Springfield as well as projections. (According to the Springfield Master Plan, the NH Office of Energy & Planning population projections for the Town of Springfield may be low.) The average number of persons per occupied housing unit was 2.45 in 2000. In 2000, there were 148 vacant units—this includes 129 seasonal units, probably used for hunting and vacation. These were assumed to be included in the U.S. Census total housing units as single-family units. It is important to consider these vacant units in hazard mitigation as they are often located near water bodies. These units may also be occupied during certain seasons of the year prone to natural hazard, e.g. vacation home occupants may be impacted by a flooding and should be included in any educational campaign for disaster preparedness.

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Table II-1: AREA POPULATION TRENDS

Area 1970 1980 Avg. Annual Growth 70-80

1990 Avg. Annual Growth 80-90

2000 Avg. Annual Growth 90-00

30 Yr. Avg. Annual Rate

Springfield 310 532 5.55% 788 4.01% 945 1.83% 3.79%Croydon 396 457 1.44% 627 3.21% 661 0.53% 1.72%Enfield 2345 3175 3.08% 3979 2.28% 4618 1.50% 2.28%Grafton 370 739 7.16% 923 2.25% 1138 2.12% 3.82%Grantham 366 704 6.76% 1,247 5.88% 2,167 5.68% 6.11%New London 2236 2935 2.76% 3,180 0.80% 4,116 2.61% 2.05%Sunapee 1,384 2,312 5.27% 2,559 1.02% 3,055 1.79% 2.67%Wilmot 516 725 3.46% 935 2.58% 1144 2.04% 2.69%Sullivan County 30,949 36,063 1.54% 38,592 0.68% 40,458 0.47% 0.90%New Hampshire 737,681 920,610 2.24% 1,109,252 1.88% 1,235,786 1.09% 1.73%Source: US Census Table II-2: POPULATION PROJECTIONS FOR SPRINGFIELD

1970 1980 1990 2000 2010 2020 2030 Population 310 532 788 945 1170 1320 1430 Decade Change in Population 73% 48% 20% 24% 13% 8% Source: 1970 – 2000 US Census & 2010 – 2030 NH Office of Energy & Planning Table II-3 : OCCUPIED HOUSING UNIT PROJECTIONS BY TYPE FOR SPRINGFIELD 2000 2010 2020 2030 Single-Family Units (.85) 328 406 458 496 Multi-Family Units (.02) 8 10 11 12 Mobile Home Units (.13) 50 62 70 76 TOTAL OCCUPIED UNITS 386 478 539 584 Source: US Census PHC 2-31Table 18 for unit type proportions in 2000; assumed all vacant units are single-family; projected totals based on persons/occupied unit (2.45) Table II-4: TOTAL HOUSING UNIT PROJECTIONS BY OCCUPANCY FOR SPRINGFIELD

2000 2010 2020 2030 Seasonal or Vacation Vacant (.24) 129 158 176 191 Other Vacant Units (.04) 19 25 29 31 Occupied Units (.72) 386 478 539 584 TOTAL ALL UNITS 534 661 744 806 Source: US Census PHC-1-31 Table 12 for 2000; total units projected as percentage of occupied units; other units projected in proportion of total in 2000.

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III. HAZARD IDENTIFICATION

The Springfield Hazard Mitigation Committee reviewed the list of hazards provided in the State of New Hampshire Hazard Mitigation Plan, and some hazard history for the State of New Hampshire and Sullivan County in particular. A list of past hazard events in Springfield, Sullivan County, and the State of New Hampshire can be found in the following discussion and tables. After reviewing this information and the Emergency Operations Plan, the Committee conducted a Risk Assessment. The resulting risk designations are provided in the heading of each hazard table below as well as a more detailed discussion further into this chapter. A. WHAT ARE THE HAZARDS IN SPRINGFIELD? Springfield is prone to a variety of natural and human-made hazards. The hazards that Springfield is most vulnerable to were determined through gathering historical knowledge of long time residents and town officials; research into the CRREL Ice Jam Database, FEMA and NOAA documented disasters, and local land use restrictions; and from the input of representatives from state agencies (NH HSEM). The hazards affecting the Town of Springfield are dam failure, flooding, hurricane, tornado, thunderstorm (including lightening and hail), severe wind, extreme winter weather (including extreme cold and ice storms), snow avalanche, earthquake, landslide, erosion, drought, extreme heat, wildfire, natural water & air contaminants, and hazardous materials spills. Each of these hazards and the past occurrences of these hazards are described in the following sections. Hazards that were eliminated from assessment are those that have not had a direct impact on the Town of Springfield and are not anticipated to have an impact as determined by the Hazard Mitigation Planning Committee, representatives from state agencies and citizens of the Town of Springfield. Eliminated hazards include Land Subsidence, Expansive Soils, and Snow Avalanches due to soils and topography not conducive to these hazards as well as relative location of existing and proposed development. B. DESCRIPTIONS OF HAZARDS An assessment of each hazard relevant to Springfield is provided below. An inventory of previous and potential hazards is provided. Past events are shown in the following tables and the potential for future events is then discussed. The “risk” designation for each hazard was determined after evaluations discussed later in this chapter.

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• Dam Failure • Severe Winter Weather • Erosion • Flooding • Earthquake • Wildfire • Hurricane • Landslide • Natural Air & Water Contaminants • Tornado & Downburst • Drought • Hazardous Materials Spill • Thunderstorm/Lightening/Hail • Extreme Heat

Dam Failure Dam failure results in rapid loss of water that is normally held by the dam. These kinds of floods pose a significant threat to both life and property. Appendices G and H provide maps with the location of dams in Springfield. Past Dam Failure Events There have been no dam failures in Springfield or any surrounding towns which impacted Springfield. Three dams were designated by the State as “low hazard potential” which means because of its location and size, a dam failure would result in no possible loss of life, low economic loss to structures or property; possible structural damage to public roads; the release of liquid industrial, agricultural, or commercial wastes under certain conditions; and reversible losses to environmentally-sensitive areas. Three dams were designated as “non-menace” which means because of its location and size, a dam failure would not result in probable loss of life or loss to property. Table III-1: DAMS – LOW RISK

DAMS (DAM FAILURE – LOW RISK) Dam # Class Dam Name Water Body Owner Status Type Impoundment Area in Acres

Height of Dam (Ft)

Drainage Area in Acres

220.01 Branch Bog Brook Branch Bog Brook Hollis Heath Active S/Earth 6.0 12 4.69 220.02 NM Branch Bog Brook Branch Bog Brook Hollis Heath Breached S/Earth 0 4 3.75 220.03 Carter Brook Morgan Brook Unknown Ruins S/Earth 0 8 0 220.04 Lake Kolelemook Lake Kolelemook Town Active Concrete 99 4.5 1.26 220.05 NM Gove Brook Gove Brook Town Active S/Earth 1.3 6 1.19 220.06 NM Gove Brook Gove Brook David Reney Breached Earth 0 8 1.38 220.07 Gove Brook Gove Brook David Reney Ruins Earth 3.5 7 0 220.08 Morgan Pond Brook Morgan Pond Brook New London Ruins S/Earth 0 10 2.3

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DAMS (DAM FAILURE – LOW RISK) 220.09 L Morgan Pond Dam Kidder Brook NL/S Water Dist Active Concrete 34 12 .87 220.10 NM Morgan Pond Brook Morgan Pond Brook NL/S Water Dist. Active Concrete 0.25 16 0 220.11 L Star Lake Dam Otter Brook Star Lk Properties Active Concrete 65.7 6.5 1.6 220.12 L Washburn Cor/Bog Br Bog Brook NH F&G Active E/C 202 135 12.1 220.13 NM Fire Pond Dam Unnamed Stream Donald Hayes Active Earth .2 6 0 220.14 NM Wildlife Pond Dam Unnamed Stream Kirk Heath Active Earth .33 10.5 0 220.15 NM Wildlife Pond Dam Unnamed Stream Charles Lawson Active Earth .16 6 0 220.16 L Bog Brook Pond Dam Bog Brook Bog Br Pd Assoc Active Concrete 17 18 .89 220.17 NM Fire Pond Dam Unnamed Stream Arnold Putney Active Earth .06 13 0 220.18 NM Kidder Brook Dam Kidder Brook NL/S Water Dist. Active Concrete 1 19 2.1 220.19 NM Bernhardy Dam Gove Brook Charles Gallup Active Earth 2 5 0 Source: Dam information provided by the NH Dam Bureau in 2007; Significant & High Hazard dams must have an emergency action plan. The State of New Hampshire classifies dams into the following four categories: Blank- Non-Active; NM – Non-menace; L – Low hazard; S – Significant hazard; H – High Hazard Type: S=stone; C=concrete; E=earth Potential Future Dam Failure Damage Although there are 19 dams in Springfield, there are no “high” or “significant” hazard dams in Springfield. No emergency action plans are required for any of these dams to delineate inundation areas. The neighboring Town of Grantham has a dam at the southern end of Eastman Pond ranked as “high hazard potential.” Appendix G is a map of the inundation area of the Eastman Dam from the Emergency Action Plan. This shows if the dam were to fail, a very small, undeveloped portion of Springfield would be impacted. Although the remainder of Springfield’s dams are not considered “high” or “significant” hazards, the Committee is concerned about the Morgan Pond Dam and the Star Lake Dam which are rated as “low” hazard. If the Morgan Pond Dam were to fail, it would travel primarily through the Gile State Forest. However, waters from the failed dam could exit the forest along the Kidder Brook to where there is substantial development on the Twin Lake Villa Road, Golf Course Road, and Route 114 to Little Sunapee Lake in the Town of New London. If the Star Lake Dam were to fail, the waters could travel downstream along Georges Mill Road to a low lying area including the Springfield Power Plan at I-89 and the town line toward Otter Pond in the Town of Sunapee. Since the perceived potential impact could be great, the Committee chose to include mention of these dams.

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Flooding Flooding is the temporary overflow of water onto lands that are not normally covered by water. Flooding results from the overflow of major rivers and tributaries, storm surges, and inadequate local drainage. Floods can cause loss of life, property damage, crop/livestock damage, and water supply contamination, and can disrupt travel routes on roads and bridges. Floods in the Springfield area are most likely to occur in the spring due to the increase in rainfall and snowmelt; however, floods can occur at any time of the year. A sudden winter thaw or a major summer downpour can cause flooding. Floodplains indicate areas potentially affected by flooding. There are several types of flooding. 100-Year Floods The term “100-year flood” does not mean that flooding will occur once every 100 years, but is a statement of probability to describe how one flood compares to others that are likely to occur. What it actually means is that there is a one percent chance of a flood in any given year. These areas were mapped for all towns in New Hampshire by FEMA. Appendix E displays the “Special Flood Hazards Areas.” River Ice Jams Ice forming in riverbeds and against structures presents significant hazardous conditions when storm waters encounter these ice formations which may create temporary dams. These dams may create flooding conditions where none previously existed (i.e., as a consequence of elevation in relation to normal floodplains). Additionally, there is the impact of the ice itself on structures such as highway and railroad bridges. Large masses of ice may push on structures laterally and/or may lift structures not designed for such impacts. A search on the Cold Regions Research and Environmental Laboratory (CRREL) and discussion with the Springfield Committee revealed that there is no history of ice jam related events in the Town. Rapid Snow Pack Melt Warm temperatures and heavy rains cause rapid snowmelt. Quickly melting snow coupled with moderate to heavy rains are prime conditions for flooding. Severe Storms Flooding associated with severe storms can inflict heavy damage to property. Heavy rains during severe storms are a common cause of inland flooding. Beaver Dams and Lodging Flooding associated with beaver dams and lodging can cause road flooding or damage to property. Bank Erosion and Failure As development increases, changes occur that increase the rate and volume of runoff, and accelerate the natural geologic erosion process. Erosion typically occurs at the outside of river bends and sediment deposits in low velocity areas at

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the insides of bends. Resistance to erosion is dependent on the riverbank’s protective cover, such as vegetation or rock riprap, or its soils and stability. Roads and bridges are also susceptible to erosion. Past Flooding Events In the spring of 2007 several roads which are not designated areas of 100-year flood were washed out. The Committee delineated all areas where flooding has occurred in recent years. Appendix E is a map which shows the locally identified flood areas and the flood Insurance Rate Map of Special Flood Hazard Areas determined by FEMA to be potential hazard zones in a 100-year flood. The following tables provide a list of floods in the State, County, and Springfield.

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Table III-2: FLOODING – FEMA DISASTER DECLARATIONS

FLOODING – FEMA DISASTER DECLARATIONS Hazard Date Location Description of Areas Impacted Damages

Flood March 11-21, 1936 NH State

Damage to Road Network. Flooding caused by simultaneous heavy snowfall totals, heavy rains and warm weather. Run-off from melting snow with rain overflowed the rivers

Unknown

Flood / Severe Storm

April 16, 1987

Cheshire, Carroll, Grafton, Hillsborough, Merrimack,

Rockingham, & Sullivan Counties, NH

FEMA Disaster Declaration # 789- DR (Presidentially Declared Disaster). Flooding of low-lying areas along river caused by snowmelt and intense rain.

$4,888,889 in damage.

Flood August 7-11, 1990

Belknap, Carroll, Cheshire, Coos, Grafton, Hillsborough, Merrimack &

Sullivan Counties, NH

FEMA Disaster Declaration # 876. Flooding caused by a series of storm events with moderate to heavy rains.

$2,297,777 in damage.

Flood October 29, 1996

Grafton, Hillsborough, Merrimack, Rockingham, Strafford & Sullivan

Counties, NH

FEMA Disaster Declaration # 1144- DR. Flooding caused by heavy rains.

$2,341,273 in damage.

Flood October 7-18, 2005

Cheshire, Grafton, Merrimack, Sullivan, and Hillsborough Counties,

NH

FEMA Disaster Declaration # 1610. Severe storms and flooding.

$30,000,000 in damages.

Flood April 16, 2007 All counties, NH FEMA Disaster Declaration # 1695. Severe storms and flooding.

$27,000,000 in damages; 2,005 home owners and renters applied for assistance in NH.

Table III-3: FEMA FLOOD INSURANCE RATE MAP SPECIAL FLOOD HAZARD AREAS

Location Description of Area Comments Stoney Brook Road Four houses See Locally Defined Flooding table Colcord and Bog Brooks/Eastman Development/Eastman Access Rd

Three houses, one mobile home, and potential for new homes in Eastman development w/private rds

Eastman Access Road has had water to edge of road; no known flooding in area

McDaniels Marsh Wildlife Management Area No structures Conserved area with no development Town Farm Road/Route 4A/Old Grafton Road 11 houses and seven mobile homes See Locally Defined Flooding table Wetland in NE corner of town No structures Area with no road access

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Table III-4: LOCALLY DEFINED FLOODING – MEDIUM RISK LOCALLY DEFINED FLOODING – MEDIUM RISK

Date Location Description of Areas Impacted Damages Occasional depending

on dam control and

weather

Golf Course Road & State Route 114 Flooding; needs a box culvert on Golf Course Road Road only

Messer Hill Road Flooding; Will replace a couple culverts

Oak Hill Road West Washed; Working on deepening ditches

Cemetery Road Some road wash; replaced a culvert

Springs of 2006 &

2007 George’s Mill Road (State road) just south of Route 114

Shoulders and part of pavement washed; took out some private driveways; ditches & culvert filled w/debris

Road only

Striker & Fisher Corner Roads at intersection Flooded road; State removed debris from culverts on Georges Mill Road—rectified problem Eastman Access Road Water up to edge of road; minor shoulder wash

Stoney Brook Road (Special Flood Hazard Area) Road flooding; only floods after major storm event

Route 4A (State road) west of Sugar House Road Washed shoulder on Sugar House Road and some pavement loss

on Rt. 4A; only an issue in severe weather though Rt. 4A impacted by lack debris removal from culvert/ditch

Town Farm Road just south of Howard Road Big swamp nearby; water from Gile Forest; culvert has filled; lost ½ road width; ditch washed out and culvert couldn’t handle water;

replaced two culverts on Town Farm Road Phillbrook Hill Road just south of George Hill Rd Portion of road wash out

Deer Hill Road Portion of road wash out

Nichols Hill Road Road wash out Town Farm Road/Route 4A/Old Grafton Road (Special Flood Hazard Area) Minor shoulder wash; could back up due to nearby beaver activity

Deep Snow Drive Subject to heavy run-off due to lay of land

Hazzard Road North Portion of road washed out; rebuilt road w/ new culverts in 2007

George Hill Road Road shoulder washed out; heavy run-off due to nearby logging and tree damage by wind

Spring 2007

Lorent Drive Some road wash; private pond overflow

Town road wash total cost around $120,000; no damage to homes

In the early spring of 2007, there were two

wet snow storms followed by rain.

Water coming down the hillsides and snow and ice in the culverts and ditches caused an

unusual amount of water in the roads

which caused substantial damage.

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Potential Future Flooding Events Future flooding is likely as noted in the above table based upon local knowledge of past flood events. The total structures in potential flood areas which are low and vulnerable to flooding include 19 houses and eight mobile homes although flooding has not damaged any of these homes as yet. Two homes are located in the Eastman development on private roads. These houses appear to be located in a FIRM special flood hazard area and are included in the FEMA list. However, they are not listed in the locally defined flooding table as the Town is not aware of flooding in this area as the Town is not responsible for maintaining the roads in Eastman. According to the State’s Mitigation Plan, Sullivan County has a high hazard risk for flooding. The Committee determined flooding is a medium risk in Springfield. Hurricane A hurricane is an intense tropical weather system with a well-defined circulation and maximum sustained winds of 74 mph (64 knots) or higher. Hurricane winds blow in a large spiral around a relative calm center known as the "eye." The "eye" is generally 20 to 30 miles wide, and the storm may extend outward 400 miles. As a hurricane nears land, it can bring torrential rains, high winds, and storm surges. A single hurricane can last for more than 2 weeks over open waters and can run a path across the entire length of the eastern seaboard. August and September are peak months during the hurricane season that lasts from June 1 through November 30. Damage resulting from winds of this force can be substantial, especially considering the duration of the event, which may last for many hours (NH Hazard Mitigation Plan; FEMA website). Past Hurricane Events There have been several hurricanes over the years which have impacted New England and New Hampshire. These are listed below. The 1938 hurricane directly impacted Springfield according to the Committee member recollections.

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Table III-5: HURRICANES & TROPICAL STORMS – LOW/MEDIUM RISK

HURRICANES AND TROPICAL STORMS – LOW/MEDIUM RISK Hazard Date Location Description of Areas Impacted Damages Hurricane August, 1635 n/a Unknown

Hurricane October 18-19, 1778 n/a Winds 40-75 mph Unknown

Hurricane October 9, 1804 n/a Unknown

Gale September 23, 1815 n/a Winds > 50mph Unknown

Hurricane September 8, 1869 n/a Unknown

Hurricane September 21, 1938 Southern New England

Flooding caused damage to road network and structures. 13 deaths, 494 injured throughout NH. Disruption of electric and telephone services for weeks. 2 Billion feet of marketable lumber blown down. Total storm losses of $12,337,643 (1938 dollars). 186 mph maximum winds.

Unknown

Hurricane (Carol)

August 31, 1954 Southern New England

Category 3, winds 111-130 mph. Extensive tree and crop damage in NH, localized flooding

Unknown

Hurricane (Edna)

September 11, 1954 Southern New England

Category 3 in Massachusetts. This Hurricane moved off shore but still cost 21 lives and $40.5 million in damages throughout New England. Following so close to Carol it made recovery difficult for some areas. Heavy rain in NH

Unknown

Hurricane (Donna)

September 12, 1960 Southern and Central NH

Category 3 (Category 1 in NH). Heavy flooding in some parts of the State.

Unknown

Tropical Storm

(Daisy)

October 7, 1962 Coastal NH Heavy swell and flooding along the coast

Unknown

Tropical Storm

(Doria)

August 28, 1971 New Hampshire

Center passed over NH resulting in heavy rain and damaging winds

Unknown

Hurricane (Belle)

August 10, 1976 Southern New England

Primarily rain with resulting flooding in New Hampshire. Category 1

Unknown

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HURRICANES AND TROPICAL STORMS – LOW/MEDIUM RISK Hazard Date Location Description of Areas Impacted Damages

Hurricane (Gloria)

September, 1985 Southern New England

Category 2, winds 96-110 mph. Electric structures damaged; tree damages. This Hurricane fell apart upon striking Long Island with heavy rains, localized flooding, and minor wind damage in NH

Unknown

Hurricane (Bob)

August 19, 1991

Southern New England; caused flooding in

Springfield

Structural and electrical damage in region from fallen trees. 3 persons were killed and $2.5 million in damages were suffered along coastal New Hampshire. Federal Disaster FEMA-917-DR

Unknown

Hurricane (Edouard)

September 1, 1996 Southern New England

Winds in NH up to 38 mph and 1 inch of rain along the coast. Roads and electrical lines damaged

Unknown

Tropical Storm

(Floyd)

September 16-18, 1999 Southern New England FEMA DR-1305-NH. Heavy Rains

Unknown

Hurricane (Katrina)

August 29, 2005 &

continuing

East Coast of US and more FEMA-3258-EM. Heavy rains and flooding devastating SE US

Unknown

Tropical Storm

(Tammy)

October 5-13, 2005 East Coast of US

Remnants of Tammy contributed to the October 2005 floods which dropped 20 inches of rain in some places in NH.

Unknown

Potential Future Hurricane Damage Hurricane events will affect the entire town. It is impossible to predict into the future what damage will occur in the town. According to the State’s mitigation plan, Sullivan County has a medium risk for hurricanes. The Committee determined the hurricane risk to be low/medium in Springfield. Tornado & Downburst “A tornado is a violent windstorm characterized by a twisting, funnel shaped cloud. These events are spawned by thunderstorms and, occasionally by hurricanes, and may occur singularly or in multiples. They develop when cool air overrides a layer of warm air, causing the warm air to rise rapidly. Most vortices remain suspended in the atmosphere. Should they touch down, they become a force of destruction.” (NH Hazard Mitigation Plan). The Fujita Scale is the standard scale for rating the severity of a tornado as measured by the damage it causes. Most tornadoes are in the F0 to F2 Class. Building to modern wind standards provides significant

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property protection from these hazard events. New Hampshire is located within Zone 2 for Design Wind Speed for Community Shelters, which suggests that buildings should be built to withstand 160 mph winds. Significantly high winds occur especially during tornadoes, hurricanes, winter storms, and thunderstorms. Falling objects and downed power lines are dangerous risks associated with high winds. In addition, property damage and downed trees are common during severe wind occurrences. A downburst is a severe, localized wind blasting down from a thunderstorm. These “straight line” winds are distinguishable from tornadic activity by the pattern of destruction and debris. Downbursts fall into two categories: 1. Microburst, which covers an area less than 2.5 miles in diameter, and 2. Macroburst, which covers an area at least 2.5 miles in diameter. Most downbursts occur with thunderstorms, but they can be associated with showers too weak to produce thunder. Past Tornado & Downburst Events The following table displays tornadoes occurring in Sullivan County between 1950 and 1995 as provided by the “Tornado Project” (www.tornadoproject.com) and the NH Natural Hazard Mitigation Plan. In 2007, a severe microburst knocked down stands of trees and damaged a house and car in Springfield. Table III-6: TORNADOES IN SULLIVAN COUNTY – LOW RISK

TORNADOS – LOW RISK Sullivan County

Date Fujita Scale Damages October 24, 1955 F0 No deaths or injuries; costs unknown July 9, 1962 F0 No deaths or injuries; costs unknown July 9, 1962 F1 No deaths or injuries; costs unknown July 18, 1963 F1 No deaths or injuries; costs unknown Potential Future Tornado Damage It is impossible to predict where a tornado or downburst will occur or what damage it will inflict. The Springfield Committee does not recall tornadoes in Springfield. The FEMA website places the State of NH in the Zone II Wind Zone which provides that a community shelter should be built to a 160 mph “design wind speed.” According to the State’s mitigation plan, Sullivan County has a medium risk for tornadoes. The Committee determined there is a low risk for tornadoes and downbursts in Springfield.

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http://www.tornadoproject.com/


Thunderstorms A thunderstorm is a rain shower during which you hear thunder. Since thunder comes from lightning, all thunderstorms have lightning. A thunderstorm is classified as "severe" when it contains one or more of the following: hail three-quarter inch or greater, winds gusting in excess of 50 knots (57.5 mph), tornado. Hail is a form of precipitation that occurs when updrafts in thunderstorms carry raindrops upward into extremely cold areas of the atmosphere where they freeze into ice. When the hail particle becomes heavy enough to resist the updraft, it falls to the ground. The resulting wind and hail can cause death, injury, and property damage. An average thunderstorm is 15 miles in diameter and lasts an average of 30 minutes. Winter thunderstorms are rare because the air is more stable, strong updrafts cannot form because the surface temperatures during the winter are colder. Lightning is a giant spark of electricity that occurs within the atmosphere or between the atmosphere and the ground. As lightning passes through the air, it heats the air to a temperature of about 50,000 degrees Fahrenheit, considerably hotter than the surface of the sun. Fires are a likely result of lightning strikes, and lightning strikes can cause death, injury, and property damage. It is impossible to predict where lightening will strike. There have probably been lightening strikes in Springfield, but there is no record of damage. Past Thunderstorm Events There have probably been lightening strikes in Springfield, but there is no record of damage. A thunderstorm with lightening or hail could impact the entire town. There have been no recalled serious hailstorms or lightening strikes in Springfield. Potential Future Thunderstorm Damage It is inevitable that thunderstorms will occur in Springfield’s future. Lightening, hail, or wind from a thunderstorm could impact the entire town. It is not possible to estimate possible damage. According to the State’s mitigation plan, Sullivan County has a medium risk of a lightening hazard. The risk for future thunderstorm damage was determined by the Committee to be low/medium risk in Springfield. Severe Winter Weather Ice and snow events typically occur during the winter months and can cause loss of life, property damage, and tree damage.

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Heavy Snow Storms A heavy snowstorm is generally considered to be one which deposits four or more inches of snow in a twelve-hour period… A blizzard is a winter storm characterized by high winds, low temperatures, and driving snow- according to the official definition given in 1958 by the U.S. Weather Bureau, the winds must exceed 35 miles per hour and the temperatures must drop to 20°F (-7°C) or lower. Therefore, intense Nor’easters, which occur in the winter months, are often referred to as blizzards. The definition includes the conditions under which dry snow, which has previously fallen, is whipped into the air and diminishes visual range. Such conditions, when extreme enough, are called “white outs.” Ice Storms Freezing rain occurs when snowflakes descend into a warmer layer of air and melt completely. When these liquid water drops fall through another thin layer of freezing air just above the surface, they don't have enough time to refreeze before reaching the ground. Because they are "supercooled," they instantly refreeze upon contact with anything that that is at or below O degrees C, creating a glaze of ice on the ground, trees, power lines, or other objects. A significant accumulation of freezing rain lasting several hours or more is called an ice storm. This condition may strain branches of trees, power lines and even transmission towers to the breaking point and often creates treacherous conditions for highway travel and aviation. Debris impacted roads make emergency access, repair and cleanup extremely difficult. “Nor’easters” Nor'easters can occur in the eastern United States any time between October and April, when moisture and cold air are plentiful. They are known for dumping heavy amounts of rain and snow, producing hurricane-force winds, and creating high surfs that cause severe beach erosion and coastal flooding. A Nor'easter is named for the winds that blow in from the northeast and drive the storm up the east coast along the Gulf Stream, a band of warm water that lies off the Atlantic coast.

There are two main components to a Nor'easter: Gulf Stream low-pressure system (counter-clockwise winds) generate off the coast of Florida. The air above the Gulf Stream warms and spawns a low-pressure system. This low circulates off the southeastern U.S. coast, gathering warm air and moisture from the Atlantic. Strong northeasterly winds at the leading edge of the storm pull it up the east coast. As the strong northeasterly winds pull the storm up the east coast, it meets with cold Arctic high-pressure system (clockwise winds) blowing down from Canada. When the two systems collide, the moisture and cold air produce a mix of precipitation.

Winter conditions make Nor'easters a normal occurrence, but only a handful actually gather the force and power to cause problems inland. The resulting precipitation depends on how close you are to the converging point of the two storms. Nor’easter events which occur toward the end of a winter season may exacerbate the spring flooding conditions by depositing significant snow pack at a time of the season when spring rains are poised to initiate rapid snow pack melting. Past Extreme Winter Weather Events The following table provides a list of past extreme winter weather events in New Hampshire and Springfield.

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Table III-7: SEVERE WINTER WEATHER – LOW/MEDIUM RISK

SEVERE WINTER WEATHER/ICE STORMS – MEDIUM RISK

Hazard Date Location Description of Areas Impacted Damages

Ice Storm December 17-20, 1929 New Hampshire

Unprecedented disruption and damage to telephone, telegraph and power system. Comparable to 1998 Ice Storm (see below)

Unknown

Blizzard February 14-17, 1958 New Hampshire 20-30 inches of snow in parts of New Hampshire Unknown

Snow Storm

March 18-21, 1958 New Hampshire

Up to 22 inches of snow in south central NH Unknown

Snow Storm

December 10-13, 1960 New Hampshire

Up to 17 inches of snow in southern NH Unknown

Snow Storm

January 18-20, 1961 New Hampshire


Snow Storm

February 2-5, 1961 New Hampshire


Snow Storm



Blizzard January 29-31, 1966 New Hampshire Third and most severe storm of 3 that occurred over a 10-day period. Up to 10 inches of snow across central NH

Unknown

Snow Storm

December 26-28, 1969 New Hampshire

Up to 41 inches of snow in west central NH Unknown

Snow Storm

February 18-20, 1972 New Hampshire


Snow Storm



Blizzard February 5-7, 1978 New Hampshire New England-wide. Up to 25 inches of snow in central NH Unknown

Snow Storm

February, 1979 New Hampshire President’s Day storm Unknown

Ice Storm January 8-25, 1979 New Hampshire Major disruptions to power and transportation Unknown

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SEVERE WINTER WEATHER/ICE STORMS – MEDIUM RISK

Hazard Date Location Description of Areas Impacted Damages

Snow Storm

April 5-7, 1982 New Hampshire


Ice Storm February 14, 1986 New Hampshire

Fiercest ice storm in 30 yrs in the higher elevations in the Monadnock region. It covered a swath about 10 miles wide from the MA border to New London NH

Unknown

Extreme Cold

November-December,

1988 New Hampshire Temperature was below 0 degrees F for a month Unknown

Ice Storm March 3-6, 1991 New Hampshire Numerous outages from ice-laden power lines in southern NH Unknown

Snow Storm 1997 New Hampshire

Power outages throughout Springfield due to heavy snowfall Unknown

Ice Storm January 15, 1998 New Hampshire; Substantial power outages in Springfield for a week

Federal disaster declaration DR-1199-NH, 20 major road closures, 67,586 without electricity, 2,310 without phone service, $17+ million in damages to Public Service of NH alone

Unknown

Snow Storm 2000 Regional; entire town of Springfield Heavy snow Unknown

Ice Storm 2004 Regional Ice storm resulted in many trees down and loss of power. Unknown

Ice Storm 2007 Springfield, Regional Ice storm resulted in many trees down and loss of power. One house and car damaged. Much tree damage

Potential Future Severe Winter Damage: There is the potential for severe winter damage every year. The event would affect the entire town. According to the State’s mitigation plan, Sullivan County has a high risk for severe winter weather. The Committee determined severe winter weather to be a medium risk in Springfield.

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Earthquake The following is a list of earthquakes which have impacted New England, New Hampshire, and Springfield. Table III-8: EARTHQUAKES – LOW/MEDIUM RISK

EARTHQUAKES – LOW/MEDIUM RISK

Date Location Magnitude Damage 1638 Central NH 6.5-7

October 29, 1727 Off NH/MA coast NA Widespread damage Massachusetts to Maine: cost unknown

December 29, 1727 Off NH/MA coast NA Widespread damage Massachusetts to Maine: cost unknown

November 18, 1755 Cape Ann, MA 6.0 Much damage: cost unknown

1800s Statewide 83 Unknown

1900s Statewide 200 Unknown

March 18, 1926 Manchester, NH Felt in Hillsborough Co Unknown

Dec 20, 1940 Ossipee, NH Both earthquakes 5.5 Damage to homes, water main rupture: cost unknown.

December 24, 1940 Ossipee, NH NA Unknown

December 28, 1947 Dover-Foxcroft, ME 4.5 Unknown

June 10, 1951 Kingston, RI 4.6 Unknown

April 26, 1957 Portland, ME 4.7 Unknown

April 10, 1962 Middlebury, VT 4.2 Unknown

June 15, 1973 Near Quebec Border 4.8 Unknown

January 19, 1982 West of Laconia 4.5 Structure damage 15 miles away in Concord: cost unknown

October 20, 1988 Near Berlin, NH 4 Unknown

April 2002 Entire town n/a Fault under Mount Kearsarge; No known damage

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Potential Future Earthquake Damage: A United States Geographic Survey mapping tool on the web (geohazards.cr.usgs.gov/ projects) projects a 5 – 6 peak ground acceleration (pga) with 10% probability of exceedance in 50 years for the Town of Springfield. This pga rating is equivalent to a Modified Mercalli Intensity of “V” with moderate perceived shaking and very light potential damage. An earthquake event would impact the entire town. According to the State’s mitigation plan, Grafton County has a medium risk for earthquakes. The Committee determined the risk to be low/medium in Springfield. Landslide A landslide is the downward or outward movement of slope-forming materials reacting under the force of gravity, including mudslides, debris flows, and rockslides. Formations of sedimentary deposits along the Connecticut River also create potential landslide conditions. Landslides can damage or destroy roads, railroads, electrical and phone lines, and other structures. Past Landslide Events: There have been no known landslides in Springfield. Potential Future Landslide Events: The best predictor of future landslides is past landslides. If any landslide events were to occur, they would be most likely in areas of very steep slope. There is little development in these areas, so no future structural damage cost due to this natural hazard is anticipated although there could be road or utility pole damage. The Committee delineated an area where a landslide could potentially occur along Route 114 next to Kolelemook Lake which includes four cottages. Another potential landslide area is at the State rest area along I-89, but this is a State concern. Another potential area is off Nichols Hill Road which would not involve any structures though utility poles could be impacted. The Committee determined there is a low risk for landslide damage. Drought A drought is defined as a long period of abnormally low precipitation. The effects of drought are indicated through measurements of soil moisture, groundwater levels and stream flow; however, not all of these indicators will be low during a drought. Costs can include loss of agricultural crops and livestock.

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Past Drought Events Springfield has not experienced a drought to the Committee’s knowledge. Table III-9: DROUGHT – LOW RISK

Date Location Description Damages 1929-1936 Statewide Regional. Recurrence Interval 10 to > 25 years

Unknown

1939-1944 Statewide Severe in southeast and moderate elsewhere. Recurrence Interval 10 to > 25 years

Unknown

1947-1950 Statewide Moderate. Recurrence Interval 10 to > 25 years Unknown

1960-1969 Statewide

Regional longest recorded continuous spell of less than normal precipitation. Encompassed most of the Northeastern US. Recurrence Interval > 25 years

Unknown

2001-2002 Statewide Affected residential wells and agricultural water sources Unknown

Potential Future Drought Damage Drought will affect the entire town. The damage will depend upon the crops being grown at the time of the drought. No cost has been assigned to residential wells going dry though new wells may have to be dug or drilled. According to the State’s mitigation plan, Sullivan County has a medium risk for drought. Extreme Heat Extreme heat is characterized by abnormally high temperatures and/or longer than average time periods of high temperatures. These event conditions may impact the health of both humans and livestock. Past Extreme Heat Events The following table lists the extreme heat events in the past which included the Northeast and New Hampshire.

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Table III-10: EXTREME HEAT – LOW/MEDIUM RISK

Date Location Description Damage

July, 1911 New England 11-day heat wave in New Hampshire Unknown

Late June to September, 1936 North America Temps to mid 90s in the northeast Unknown

Late July, 1999 Northeast 13+ days of 90+ degree heat Unknown

Early August, 2001 New Hampshire Mid 90s and high humidity Unknown

August 2-4, 2006 New Hampshire Regional heat wave and severe storms Unknown

Potential Future Extreme Heat Events Extreme heat would impact the entire town though those with air conditioning in their homes would have less impact. The costs of extreme heat are most likely to be in human life. The elderly are especially susceptible to extreme heat. The State did not develop a county risk factor for extreme heat in its NH Hazard Mitigation Plan. The Committee determined extreme heat to be a low/medium risk in Springfield. Erosion

Soil erosion, although a natural process, can be greatly accelerated by improper construction practices. Because of the climate in New Hampshire and the general nature of our topography, eroded soils can be quickly transported to a wetland, stream, or lake. The New Hampshire Department of Environmental Services (DES) regulates major construction activities to minimize impacts upon these resources. A properly conducted construction project should not cause significant soil erosion.

Soil becomes vulnerable to erosion when construction activity removes or disturbs the vegetative cover. Vegetative cover and its root system play an extremely important role in preventing erosion by: (1) Shielding the soil surface from the impact of falling rain drops; (2) Reducing the velocity of runoff; (3) Maintaining the soil's capacity to absorb water, and (4) Holding soil particles in place.

Because of the vegetation's ability to minimize erosion, limiting its removal can significantly reduce soil erosion. In addition, decreasing the area and duration of exposure of disturbed soils is also effective in limiting soil erosion. The development and building

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designer must give special consideration to the phasing of a project so that only those areas actively under construction have exposed soils. Other factors influencing soil erosion are: (1) Soil types, (2) Land slope, (3) Amount of water flowing onto the site from up-slope, and (4) Time of year of disturbance. Past Erosion Events A housing development on Oak Hill has caused substantial erosion in the area due to housing constructed on steep slopes. This has impacted the adjacent roads in the area by making them more susceptible to erosion and wash out. Run-off from steep slopes with little vegetation moves more quickly and can cause more damage. Potential Future Erosion Events Since the zoning ordinance does not restrict development in steep slopes, it is anticipated that similar situations could arise in other areas of the town unless the ordinance is amended to prevent this type of development. Wildfire Wildfire is defined as any unwanted and unplanned fire burning in the forest, shrub or grass. Wildfires are frequently referred to as forest fires, shrub fires or grass fires, depending on their location. They often occur during drought and when woody debris on the forest floor is readily available to fuel the fire. The threat of wildfires is greatest where vegetation patterns have been altered by past unsafe land-use practices, fire suppression and fire exclusion. Vegetation buildup can lead to more severe wildfires. Increased severity over recent years has decreased capability to extinguish wildfires. Wildfires are unpredictable and usually destructive, causing both personal property damage and damage to community infrastructure, cultural and economic resources. Negative short term effects of wildfires include destruction of timber, forage, wildlife habitats, scenic vistas and watersheds. Some long term effects include erosion and lowered water quality. There are many types and causes of fires. Wildfires, arson, accidental fires and others all pose a unique danger to communities and individuals. Since 1985, approximately 9,000 homes have been lost to urban/wild land interface fires across the United States (Northeast States Emergency Consortium: www.nesec.org). The majority of wildfires usually occur in April and May, when home owners are cleaning up from the winter months

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